18525387664 has 45 divisors (see below), whose sum is σ = 41761601361. Its totient is φ = 7937818560.

The previous prime is 18525387637. The next prime is 18525387677. The reversal of 18525387664 is 46678352581.

It is a happy number.

The square root of 18525387664 is 136108.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 17032338064 + 1493049600 = 130508^2 + 38640^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3808594 + ... + 3813454.

Almost surely, 2^18525387664 is an apocalyptic number.

18525387664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

18525387664 is the 136108-th square number.

It is an amenable number.

18525387664 is an abundant number, since it is smaller than the sum of its proper divisors (23236213697).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18525387664 is an frugal number, since it uses more digits than its factorization.

18525387664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9744 (or 4870 counting only the distinct ones).

The product of its digits is 9676800, while the sum is 55.

The spelling of 18525387664 in words is "eighteen billion, five hundred twenty-five million, three hundred eighty-seven thousand, six hundred sixty-four".